Giménez Xavier, PolPros, EvaAza, AnaMoran, SebastianTonda, RaúlEsteve-Codina, AnnaDabad, MarcSánchez Céspedes, Montse2019-11-272019-11-272018Gimenez-Xavier P, Pros E, Aza A, Moran S, Tonda R, Esteve-Codina A et al. Deep analysis of acquired resistance to FGFR1 inhibitor identifies MET and AKT activation and an expansion of AKT1 mutant cells. Oncotarget. 2018; 9(59):31549-58. DOI: 10.18632/oncotarget.258621949-2553http://hdl.handle.net/10230/43004The development of acquired resistance (AR) to tyrosine kinase inhibitors (TKIs) of FGFR1 activation is currently not well understood. To gain a deeper insight into this matter in lung cancer, we used the FGFR1-amplified DMS114 cell line and generated multiple clones with AR to an FGFR1-TKI. We molecularly scrutinized the resistant cells, using whole-exome sequencing, RNA sequencing and global DNA methylation analysis. Our results show a de novo activation of AKT and ERK, and a reactivation of mTOR. Furthermore, the resistant cells exhibited strong upregulation and activation of MET, indicating crosstalk between the FGFR1 and MET axes. The resistant cells also underwent a global decrease in promoter hypermethylation of the CpG islands. Finally, we observed clonal expansion of a pre-existing change in AKT1, leading to S266L substitution, within the kinase domain of AKT. Our results demonstrate that AR to FGFR1-TKI involves deep molecular changes that promote the activation of MET and AKT, coupled with common gene expression and DNA methylation profiles. The expansion of a substitution at AKT1 was the only shared genetic change, and this may have contributed to the AR.application/pdfeng© Gimenez-Xavier et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License 3.0 (CC BY 3.0) (http://creativecommons.org/licenses/by/3.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.http://creativecommons.org/licenses/by/3.0/info:eu-repo/semantics/articlehttp://dx.doi.org/10.18632/oncotarget.25862Lung cancerFGFR1Acquired resistanceTyrosine kinase inhibitorCell linesinfo:eu-repo/semantics/openAccess